SUSE Manager webUi fails with 404

SUSE Manager 4.3

Accessing WebUI of SUSE Manager 4.3 fails with HTTP error code 404 - not found.

Checking tomcat log file catalina.out the following error message can be seen:

07-Apr-2025 10:58:46.296 SEVERE [main] org.apache.catalina.core.StandardContext.startInternal One or more listeners failed to start. Full details will be found in the appropriate container log file
07-Apr-2025 10:58:46.304 SEVERE [main] org.apache.catalina.core.StandardContext.startInternal Context [/rhn] startup failed due to previous errors

Checking tomcat log file localhost.log the following error message can be seen:

07-Apr-2025 10:58:46.280 SEVERE [main] org.apache.catalina.core.StandardContext.listenerStart Exception sending context initialized event to listener instance of class [com.redhat.rhn.webapp.RhnServletListener]
        java.lang.IllegalArgumentException: Unable to parse setting "port.number" from '0'
                at com.impossibl.postgres.system.Setting.fromString(Setting.java:692)
                at com.impossibl.postgres.system.Settings.get(Settings.java:149)
                at com.impossibl.postgres.jdbc.AbstractDataSource.buildConnectionSpecifier(AbstractDataSource.java:145)
                at com.impossibl.postgres.jdbc.AbstractDataSource.createConnection(AbstractDataSource.java:117)
                at com.impossibl.postgres.jdbc.PGDataSource.getConnection(PGDataSource.java:71)
                at com.impossibl.postgres.jdbc.PGDataSource.getConnection(PGDataSource.java:63)
                at com.suse.manager.reactor.PGEventStream.<init>(PGEventStream.java:106)

Correct database configuration from postgres database  in /etc/rhn/rhn.conf e.g .the default is:

db_host = localhost
db_port = 5432

The host and port configuration from postgres database was removed in /etc/rhn/rhn.conf:

db_host = 
db_port =